Genomic Heterozygosity
The best way to determine genomic heterozygosity is to analyse SNP (single nucleotide polymorphism) arrays or genome sequencing by WGS (‘whole genome sequencing’) by looking at as many individual SNPs as possible that are evenly distributed across the genome.
Genetic Variability and Fitness
Higher levels of genomic heterozygosity are generally associated with greater genetic variability within an individual. This variability is crucial because it can enhance the organism's ability to adapt to environmental changes and resist diseases. For example, individuals with greater heterozygosity may have a lower risk of recessive genetic disorders, as the presence of diverse alleles can mask deleterious mutations.
Association with Health and Longevity
Research has shown that individuals with higher genomic heterozygosity tend to have better health outcomes and greater longevity. Healthy ageing appears to be directly correlated with increased heterozygosity by maintaining genetic variants that play a protective role against age-related diseases as a result of diversity.
Implications for Breeding and Conservation
In animal breeding and conservation genetics, measuring genomic heterozygosity can inform breeding strategies aimed at maintaining or enhancing genetic diversity. This is particularly important in endangered species or livestock populations, where inbreeding can lead to reduced fitness and increased susceptibility to diseases. By monitoring heterozygosity levels in combination with other Inbreeding parameters (genomic inbreeding coefficient, ROH profiles) breeders can make informed decisions to avoid inbreeding and promote genetic health.
Understanding Population Structure
Genomic heterozygosity can also provide insights into the population structure and evolutionary history of a species. By comparing heterozygosity levels across different populations, researchers can infer patterns of migration, adaptation, and genetic drift. This information is vital for understanding how populations respond to environmental pressures and for developing effective conservation strategies.
Determination of genomic heterozygosity
The HE value is calculated as part of the ‘Inbreeding&Fitness’ assessment. Generatio carries out SNP array typing for this purpose.
The "Inbreeding&Fitness" assessment is currently available for dogs, horses and camels >> SHOP